Google has introduced new formats for its Ad Links (Which run on the sites of the publishers participating in its AdSense Program) -

(468x15) Displays up to 5 links


(468x15_4) Displays up to 4 links


(728x15) Displays up to 5 links


Displays up to 4 links


I really can't comment if this ad format is anyway effective from an advertisers' standpoint as adwords (as I had tried to find it) doesn't give a way to drill down to adtyped in your stats but from a standpoint of a publisher, it was not much effective for me.